Re: [ieee-ietf-coord] Rationale for 0xFFFE as octets 4 and 5 pf EUI-64?

Donald Eastlake <d3e3e3@gmail.com> Mon, 25 June 2018 00:52 UTC

MIME-Version: 1.0
In-Reply-To: <70d78698-7ec3-3a6e-3200-a958ba520141@earthlink.net>
References: <TU4PR8401MB06214FDFC0652364F7728557ED750@TU4PR8401MB0621.NAMPRD84.PROD.OUTLOOK.COM> <70d78698-7ec3-3a6e-3200-a958ba520141@earthlink.net>
From: Donald Eastlake <d3e3e3@gmail.com>
Date: Sun, 24 Jun 2018 20:52:25 -0400
Message-ID: <CAF4+nEEYtZ4diFxLDtwKT=jxXzoyPxmSK3HPKeGHhaDzQKcquQ@mail.gmail.com>
To: Charlie Perkins <charles.perkins@earthlink.net>
Cc: "ieee-ietf-coord@ietf.org" <ieee-ietf-coord@ietf.org>
Content-Type: multipart/alternative; boundary="00000000000079d67e056f6cccb0"
Archived-At: <https://mailarchive.ietf.org/arch/msg/ieee-ietf-coord/9i1HQEJByqiRtl2BVW-D82xTySg>
Subject: Re: [ieee-ietf-coord] Rationale for 0xFFFE as octets 4 and 5 pf EUI-64?
Precedence: list

Hi Charlie,

As I recall, there is/was this distinction between MAC-48 and EUI-48
addresses. I think MAC-48 was just for hardware and EUI-48 was for other
devices and software. Anyway, you inserted 0xFFFF to convert a MAC-48 to
and EUI-64 and 0xFFFE to convert an EUI-48 to an EUI-64. The RFCs that talk
about extending a 48 bit address to 64 bits to use as the low order bits of
an IPv6 address say that 0xFFFE was used by mistake and that 0xFFFF should
have been used (see for example the Note on page 22 of RFC 4291) but it was
decided to stick with 0xFFFE for that purpose. Hope this helps.

Thanks,
Donald
===============================
 Donald E. Eastlake 3rd   +1-508-333-2270 (cell)
 155 Beaver Street, Milford, MA 01757 USA
 d3e3e3@gmail.com

On Fri, Jun 22, 2018 at 9:54 PM, Charlie Perkins <
charles.perkins@earthlink.net> wrote:

> Hello folks,
>
> Does anyone here remember why 0xFFFE were chosen to be the filler bits
> (i.e., bytes 4 and 5 of 8) when expanding a 48-bit MAC address to be
> EUI-64?  It is not explained in RFC 2464.
>
> Or maybe there was not a reason...?
>
> Thanks in advance,
> Charlie P.
>
> _______________________________________________
> ieee-ietf-coord mailing list
> ieee-ietf-coord@ietf.org
> https://www.ietf.org/mailman/listinfo/ieee-ietf-coord
>

Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Pascal Thubert (pthubert)
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Robert Grow
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Roger Marks
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Pascal Thubert (pthubert)
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Robert Grow
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Pascal Thubert (pthubert)
Re: [ieee-ietf-coord] Doodle poll to schedule Lat… Stanley, Dorothy
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Robert Grow
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Russ Housley
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… ROBERT GROW
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… ROBERT GROW
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Charlie Perkins
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Pascal Thubert (pthubert)
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Charlie Perkins
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Donald Eastlake
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Donald Eastlake
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… John Messenger
[ieee-ietf-coord] Rationale for 0xFFFE as octets … Charlie Perkins
[ieee-ietf-coord] Doodle poll to schedule Late Ju… Stanley, Dorothy
Re: [ieee-ietf-coord] Rationale for 0xFFFE as oct… Geoff Thompson
[ieee-ietf-coord] Whether or not RFC 4944 can pro… Charlie Perkins
Re: [ieee-ietf-coord] Whether or not RFC 4944 can… Pascal Thubert (pthubert)
Re: [ieee-ietf-coord] Whether or not RFC 4944 can… Charlie Perkins